The first underground nuclear test took place on November, 19 1951 and was the Uncle test. Trinity test happened in July 1945 though. Answer D “The bomb was detonated underground in accordance with the Limited Test Ban Treaty” is not true concerning the first test bomb detonation at Trinity Site.
At 05:29:45 local time, the device exploded with an energy equivalent to 19 kilotons, equivalent to 19,000 tons of TNT (87.5 TJ). He left a crater in the desert soil 3 meters deep and 330 meters wide. At the time of the detonation, the surrounding mountains were illuminated for one to two seconds. The observed colors of the illumination varied from purple to green, and finally to white. The explosion of the explosion took 40 seconds to reach the observers and the shock wave could be felt 160 kilometers away. The mushroom cloud reached 12 kilometers. In the crater, the desert sand, composed mainly of silica, melted into a light green glass, which was called trinitite.
